I just changed my motor oil at 141,000 miles Using penzoil 10w-40 fully synthetic and also used lucas engine restorer ....(great stuff), I changed the oil filter with a oem one....did everything right, Oh aND I didnt forget the drain plug seal this time....My lifters are noisy at start-up and then become very subtle But I can still hear it and it is annoying the f*** outta me....Last oil change I did 2,900 miles ago I used mobil 10w-30 fully synthetic with no problems at all.....I don't get what the deal is...any reccomondations?

The problem with the hlas is the get clogged and won't pump up. I haven't taken them apart, you can disassemble the larger Mazda hlas and clean them. Don't know if it applies to the Miata's hlas. Problem is, it's a lot of work- worth the price of new ones is what you have to decide. If they're not pumping up, you are losing valve lift and that means losing power. Cleaning HLAs

You can try running some engine cleaner through for just a recommendation. Sometimes with hydraulic lifters, they just need to have all the gunk dissolved using seafoam, and then running a motor flush. Hydraulic lifters are not known for the longest life span either, or at least in the domestic world.

I use 15w50 mobil all year round. I never get any lifter noise. If you have lifter noise i would flush your engine...use some ATF and run the engine on that for about 15min and then drain it all out. Either that or you can just get some engine flush and do the same process. You likely have something obstructing the HLA oil passages and thats causing the lifter noise you are hearing.

My motor with 75k on it was loud as hell no matter what. This new engine mileage unknown ticks for 3-10secs and is quiet. My alternator belt on the other hand needs replacing and sounds like marbles...

Gunk engine flush about every 3rd or 4th depending on how long its been, you add to the old oil idle for 5 min, drain. dont rev just idle. then I fill with green cap mobil1. I did the engine flush about 3 times (3 seperate oil changes in a row) before my tick went away, this seems to keep it from coming back like it was. now only ticks when I lag on the oilchange about 500-1k miles over.